1. Field of the Invention
The present invention relates to transmitting data wirelessly, and in particular relates to transmitting data from within an enclosed touch sensing surface of an input device.
2. Description of the Related Art
The computer mouse revolutionized desktop computing, and the touch screen subsequently revolutionized mobile computing. These two types of input system highlight the importance of user input devices, and demonstrate their ability to transform advanced technologies from expensive scientific tools into low cost everyday items. In spite of diverse research efforts, there is no standard input device for navigating three-dimensional virtual environments. Virtual worlds are presented with increasingly high quality due to the decreasing cost of graphics processors, which are subject to Moore's law. Displays more than a meter across are commonplace consumer products. However, virtual environments displayed on them must be navigated using a joystick, or a mouse and keyboard, or using any one of several input technologies specialized for a particular application.
Examples of virtual environments include many kinds of computer games, three-sixty degree videos and photographs. Anyone with a web browser can, in theory, rotate, zoom and otherwise navigate these immersive experiences using a keyboard and mouse. However, this method of navigation is very cumbersome. Similarly, a smartphone can be used to view three-sixty videos by holding the device in the air and rotating it as if it were a virtual window. This viewing method is tolerable for a few tens of seconds, and serves primarily as a technology demonstrator.
One attempt to make virtual environments more comfortable is to use a virtual reality headset, which replaces most of the user's field of view with a pair of synthetic images, one for each eye. Head movements are tracked so that the images supplied to each eye are updated as if the user is actually in the virtual environment. Although the sense of immersion can be profound, it is easily broken when moving around the environment, due to the nature of input devices used to facilitate movement. Furthermore, a headset cuts the user off from their social environment, and may be uncomfortable to wear for extended periods of time. User movement in a virtual environment is known as locomotion, and the problem of locomotion in virtual reality (VR) is widely considered to be a fundamental obstacle to its wider adoption. However, more generally, user movement in any kind of three-dimensional virtual environment lacks a widely accepted universal input device analogous to the mouse or touch screen. This problem exists regardless the type of display system used.
In U.S. Pat. No. 6,891,527 B1 a hand-supported sphere is proposed as a universal input device. Passive acoustics are used to track the movement of a fingertip across the sphere's surface. The passive acoustic sensor aims to solve a particular problem: When using the sphere for input, it is rotated arbitrarily. Therefore, the entire surface must be activated uniformly for touch detection, otherwise a particular orientation would result in a user input gesture being impossible or difficult to detect. The touch-sensitive spherical surface encloses a radio transmitter that transmits gesture data to an external processing system. A resistive or capacitive touch-sensing matrix would act as a Faraday cage, attenuating or preventing radio transmissions from the input device being received. The passive acoustic system avoids this problem. However, passive acoustics relies on the sound created by a finger movement or tapping, and is limited in the vocabulary of gestures that can be detected.
Spherical input devices have been subsequently disclosed in US 2012/0154267 A1, US 2013/0027299 A1, US 2015/0054633 A1 US 2015/0097774 A1, WO 2007/077124 A1, and EP 3 190 483 A1. These documents describe freely-held spherical input devices that include one or more pressure sensors for detecting a force applied by squeezing the surface. The pressure sensors are sparsely located, avoiding the need to transmit radio signals through the conductive matrix of a resistive or capacitive touch sensor that fully covers the surface. However, squeezing is not as easy to do as touch, and these devices also have a relatively limited gestural vocabulary. In WO 2011/011898 A1 and https://lauralahti.com/The-Smartball, a freely held spherical input device is described, but these documents do not address the technical problem of providing a touch sensor that fully covers a spherical surface.
The potential of a spherical input device for universal input is significantly limited by the kinds of gestures that known systems can detect, especially compared to the sophisticated touch screen interactions, such as pinch and zoom, that most people are now familiar with.